billion

Everyday

1. A billion is one thousand million: 1,000,000,000. tree →
2. Billions means a huge, uncountable-feeling number of things. tree →

In the lessons

In maths lessons a billion is written 1,000,000,000 — a one with nine zeros, or a thousand millions. In science the Earth is about 4.5 billion years old and there are about 8 billion people. In everyday talk «billions» means very many. Phrases: a billion, billions of, two billion.

Examples

• A billion is a thousand million. tree →
• There are about eight billion people in the world. tree →
• The Earth is about four and a half billion years old. tree →
• Write one billion with nine zeros. tree →
• There are billions of stars in our galaxy. tree →
• The bridge cost two billion dollars. tree →
• I've told you a billion times! tree →
• Michael was ready: he wanted to see how long it took him to do a billion miles. tree →

Note

After a number, no «s»: «three billion people», not «three billions». Use «billions of» only without a number. Today a billion always means 1,000,000,000 (nine zeros); in old British books it once meant a million million. Order: thousand (3 zeros), million (6), billion (9), trillion (12).